Cagayan Valley's Floods Are Unprecedented. How Did It Get This Bad?

As electricity is being steadily reconnected in Luzon following the devastating aftermath of Typhoon Ulysses, Filipinos are quickly catching up to the catastrophic state of Cagayan Valley (Region II), where thousands of Filipinos are still stranded days after Ulysses left the Philippine Area of Responsibility.

This is everything we know so far.

What is happening in Cagayan?

Many areas of Cagayan Valley, Region II, were flooded due to Typhoon Ulysses, particularly the provinces of Isabela and Cagayan. In the latter province, the capital city of Tuguegarao is the worst hit and thousands have been waiting for rescue in their homes and on top of their roofs.

According to Cagayan Governor Manuel Mamba in an interview with dzBB, this is the worst flooding in Cagayan in memory. Rescue teams have been working 24/7 yet efforts during the night have been sorely limited due to total lack of visibility. The governor explained that the region did not feel the typhoon strongly, so they were blindsided by the intensity of the flood.

The nearby Magat Dam has also been forced to open its floodgates to prevent overflowing, inadvertently increasing the level of the flood. The people of Cagayan are appealing to officials at the dam to close the gates.

In some areas, the flood is so high that it has reached electrical cables. The combination of live wire and water has already electrocuted and killed several residents. The LGU is appealing to the national Grid Corporation of the Philippines to turn off power so the rescue team can enter these danger zones and save the people who remain.

The water level below the Buntuan Bridge in Tuguegarao City is already at critical level as the water threatens to overflow the bridge. The water level is at 12.8 meters, and the bridge’s limit is 13 meters.

Why did we only find out about this now?

Electricity lines are down, signal is unstable, and stranded individuals have run low on battery, making communication with the region difficult. Quarantine restrictions in the region have also limited inter-region travel for media and aid workers as COVID-19 is still rampant.

At the moment, the Cagayan Provincial Information Office and Philippine Information Agency Isabela are the best source of information.

How many people have died or are stranded?

The final tally remains uncertain as it is assumed some residents have lost connection or battery. However, according to the Cagayan PIO, the number of affected individuals is almost 85,000. More than 37,000 have been rescued. All municipalities in the province had been inundated.

As for casualties, the region records eight in Cagayan. The main causes of death have been drowning and electrocution.

It is unknown how many have died in Isabela. It’s also unclear how many have died in Marikina, Rizal, and other areas due to Ulysses flooding as government agencies are reporting different numbers. Once information is centralized, which might take a few days, it will become clearer how many were killed and injured due to flooding.

The number of those in need of rescue is beyond the capacity of the local rescue teams, and the region is appealing for helicopters to join the effort as some areas are inaccessible by land or water.

Evacuation centers are already full, so Cagayan and Isabela homes are opening their doors to neighbors, however this also increases the worry of COVID-19.

Why do the dam’s floodgates need to be opened?

At one point, seven gates of Magat Dam were opened. As of press time, only three are open. The water level is currently at 192 meters, however, the Magat Dam’s spilling level is 193 meters. When a dam’s water level is critical, like at Magat Dam, its gates must be opened to prevent spilling and going beyond the dam’s capacity.

The result is inevitable flooding in the nearby low-lying communities, who are now appealing to close the gates.

However, when a dam’s water level goes beyond its capacity, the pressure of tons of water being held can cause structural damages to the dam. This could potentially lead to a dam failure or dam burst, which will cause an uncontrolled release of massive amounts of water. Dam failures are rare, however they can cause incomparable damage and loss of life. In short, a dam is not foolproof and it can collapse.

How did deforestation make it worse?

The location of Cagayan province makes the area a catch basin for rain water in Cagayan Valley and Cordillera. Flooding is common in this area, and residents have learned to adapt to the relatively manageable flooding every year.

But the Cagayan governor noted that this year’s flooding is “unusual,” which he attributes to over 50 years of illegal logging occurring in Cagayan’s forests in the Sierra Madre.

“Inabuso ang mga kagubatan sa Cagayan kaya nagdulot ng pagbaha,” said the governor to dzBB.

Stronger and more frequent typhoons, a byproduct of climate change, over the last century have also taken its toll on Luzon. The soil, which has been saturated by constant rain in the last few months, was unable to absorb rain water in Cagayan and in Marikina, which is why flooding occurred quickly. These areas only needed a relatively small amount of rain to overflow.

Forests, soil, and mountain ranges—these are all nature’s barriers and defenses against natural disasters, yet unchecked human activity have reduced their effectivity, putting millions at risk.